Recovery of ammonia from distillers&#39; washes.



JEAN EFFRONT, or snusisnlis, sELoiUM.

RECOVERY OF AMMONIA FROM nrfsrrnnsns" wssms.

Specification of Letters Patent.

Patented Oct. 22, 1907 Application filed December 13, 1906. $erislhlo. 347,613.

To all whom it may concern;

Be it known that l, JEAN EFFRONT, doctor, a subject of the Russian Emperor, and residing at Brussels, in the Kingdom of Belgium, have invented a new and useful Recovery. of Ammonia from Distillers Washes; and I do hereby declare the following to be a iull, clear, and exact description of the same.

Heretoi'ore concentrated distillers washes have (with or without addition of lime.) been distilled directly for the purposeiof recoveringythe nitrogen in the form of ammonia. Such distillations have been without practical results, because only a very small quantity of nitroger. is extracted; moreover the product thus obtained by distillation contains large quantities of ammonia in combination with other materials and which cannot be easily utilized. These objections are due to the complex composition of the nitrbgenous substances contained in the Washes. In they are in the state of ainins, amids and amido acids, as well as in the state of albuminoid substances, and large quantities thereof i i are combined with alkaline bases. The resistances of these different combinations to the action of heat. be-

ing different, their transformation into ammonia by a single operation is difficult and incomplete. My present invention has for its object to provide an improved method 01' converting the nitrogenous substances of the distillers washes into ammonia, and consists in carryingout the distillation in two successive operations, the first employing an acid medium, and the second employing aneutral medium.

By distilling in an acid medium, at a temperature of abov- 10 or 200 C. nitrogenous substances combined with alkaline bases will be set free in the state of ammonia which produces with the volatile acids of .the washes, ammoniacal compounds (volatile at 180200 C.) and is carried away by a current 01' superheated air. By this treatment, the distillers Washes lose about 15 to 70% oi their nitrogen. After this iirstdistillation, there remains a nitrogenous residue (containing the remaining to 30% of nitrogen), which has a coal-like appearance. When this residue'is calcined in presence oi acid, the nitrogenous substances oi the residue are converted into nitrogen, cyanids and a small quantity of ammonia. On the other hand, the calcination in neutral medium, in the presence of superheated air,

results in the extraction of nearly the whole quantity o?- rernaining nitrogen in the state oi ammonia. By these two successive distillations when carefully carried out, 98 7!; of the total quantity of nitrogen will be recovered from distillers washes in the state of ammonia.

F or acidifying the washes, with a View to removing the nitrogenous substances in the first distillation,

above described, I use acid salts such as bisulfate, su-

perphosphate and the like or mineral acids. However, for these acid salts ,or acids, I may substitute resins which, owing to their acid character, produce the same effect as acid salts. In fact, the alkaline bases, such as potash and soda, are combined in distillers washes with amide acids, and when resin (colophony) which is composed of a large quantity of abietic acid (not volatile at 200- C.) is added thereto, said bases will .be combined with this abietic acid to form soap (fixed at 200 0.), while the amide acids are set free and con verted into ammonia. Therefore, colophony acts in this reaction like mineral acids or acid salts.

1 preferably substitute resins in mineral acids or acid salts, because these acids or acid salts form sul-,

fates or chlorids of soda. or potash, the commercial value of which is inferior to that of carbonate of potash or soda easily obtained by using resins and decomposing the' resinous alkaline soap formed by combina- 7 tion of resin with alkaline basesv The method isrealized difierently according to the,

washes to betreated. For treating washes of com, I preferably use bisulfate of soda. For treating washes of molasses orbeets, I preferablyuse resin (colophony) which forms soap with the bases combined with the nitric substances, and said soap may be easilyconverted to carbonate.

The'quantity of acid to be used must be chosen according to the proportion of alkaline substances con-' tained in the washes. Practically, for determining this quantity of acid, by means of preliminary experiments" on the washes to be treated, l preferably proceed as follows: In each of a series of glass receptacles I place 100 grams of washes to b treated, and dilierent and dotcrmined quantities of. acid or acid salts. These receptacles are placed in a stove and heated for 5 hours, to a temperature of 190 0., superheated, air being passed through each receptacle. Thereafter the acidity of the washes contained in each receptacle is ascertainedz The quantity of acid or acid salt to be used for carrying the method corresponds to that which has been placed into the receptacle, the washes of which contain, after the said operation 2 to 4 grams of acid (sulfuric acid) per grains of substances. In one form, this present method or process is carried out as iollowsz-The washes are concentrated to 40 or 42 Baum. Then I add thereto the quantity oi'acid or acid salt (varying for illstance from-10 to 30 kgrs. oi bisulfate for 1000 kgrs. of concentrated washes) determined by the'preliminary experiment, above described, and the mixture is dried. For this purpose the liquid is maintained heated at 180 or 200 (J.. This operation. is preferably carried on in a stove through which a current of superheated air is passed, and the products of distillation are collected into washers. The heating of the washes within the stove is continued until they have lost about one halt oi their weight. The liquid which is distilled during "thedrying operation has, at a given moment, an acid treated,- but inay'reach6073' and =e\ en 75%. 'The residue remaining in the tove is a melted porous inass' containing-all thes 'aline and nitric 'oiganic substances In o rde r'toiextrgct the nitrogenifromthie residue, I crush the pmpus mas and add suificientgbarbonate of lime for its 1i eutraliz ation,f and I then place the mixture into irqn-retorts agranged' WitEin-a fumace 4.10 1

.'-' li a of! P P is clzlim and desire to s ecureby Letters Patentjis'z "passedthmugh'the mass;and the distilled'products are and heated to the temperature oi -700 During the collected into acid coudefieatprs. Among the-products of distillaticnis methylicFalcohbl.whichyin certain cases, may'beektractdjtoz ether purposes. The two fd'istinct oper'aticnis chamacteristic of the 'improved prqcese herein described. (the. drying opera mass) relateespecially to distillei s washes treatet lwith;

- pulvel ize abietic-acidf ud heated i ia teyeflto' Stemperature of about 290?). 'duting S r' 41191113, During this time,-c1i1j'*rents qisiuperhea tedaiid and cax bcnic gas arecaused t i pass'altetnatebfl-tlj roughthe 'stove The disitilled 'liquidlis collected iu acid. The remaining 'is again collected, after which it nitric substance, which is insoluble in Water, remains on the fi1te1 This submas's compo'sed ufjres'inbu sca p,-

audaorgaui c' sub: stances, after being dried, is tr eatedfwitlt hot Water-:1 The resin floating un the urfaceistheu' decanted and.

the li u d; filtered t rou h lineil; T ma er'igtlre,

taiued onfthe' filteris tfea'tedwith limejn brder'to cle comggsethe resinous-563p, and the'resin thus liberated stance is first driedin'the stovelat a. te'mpe'mturebf 1009 (1., and then tfeated as abb've desc ibed iii retortg heab" isteam'dud air, H v, f

.jlutreatiug cert n mqlasses it"m'ay be ad ntggecus' to remdve the salt from the mass which has been 'inaiin tained at a temperature of 180? C separation may I be effected 'easilyes the, nitrege'u is in anf insoluble fstate: A;1l thenhecessry isfto vdiss olye 'thesalt in hot v Wa te: tqr.seperqtiugtheffrom the uitrie substaucq v. I which :is'utilize d afterwardef Haviugthui fully described ruyliuventiciigwl at I sists indecomposing the alkaline oi giuic Substancescon- .tainedlin ecu cntl at ed washes then distilling at -a low temperature, and collecting thyptodhc'ts bf distillation;

- DGlSBtUI'B'IOf 700"" C. ,"'and, during snch"hesitlug 'subjecttilg "the massilto'th'action OfsupeYheate'd'steam amd' air, andcollecting the productspt distillation; f The procesg ofutiliziug' distillerswqasheg whtcp con ists' in deccmpcsihg thetalkzilin'e; brgunic, substances con tained in.cucentmtediwgighes; theu'distilling, in the unrL d urding such heat- I ing, sub'j ec'tiug themaSs-to.the'iictiqu df superheated teatu,

odimts 'of distillation;

.7 The l-mess. o utilizing djt'iller s washes, which' cdm s i'sts.1n :tre:iting concentrated Was'he with 'matei-iatof an acid character ,foi. de'cmp'dsingfthe ';1lkati1ie Oligftnlc :suiJ- stance coutiiiued iusaidfwashesidistillingatelow Itemperalture andcbllecting the products'i qf distillatiou; neutralizing the dried residue 'aud'hegtttng 'it,:.while subjecting the mags to the aetionofns'uperheat-ed 'steam andaii', and collecting the "productsfof distillation; 1 in testimonywhereof, Ita i si'g nedjn y ni me t0,1.11isspecifieatiou iu-thepresenee ut tyjdsubscribingwitnesses. I

I i ='JEAN EEFRONT'. 

